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<FONT color="green">001</FONT>    <a name="line.1"></a>
<FONT color="green">002</FONT>    /*<a name="line.2"></a>
<FONT color="green">003</FONT>     * Copyright (C) 2011 Archie L. Cobbs. All rights reserved.<a name="line.3"></a>
<FONT color="green">004</FONT>     *<a name="line.4"></a>
<FONT color="green">005</FONT>     * $Id: MainClass.html 61 2011-03-10 15:40:08Z archie.cobbs $<a name="line.5"></a>
<FONT color="green">006</FONT>     */<a name="line.6"></a>
<FONT color="green">007</FONT>    <a name="line.7"></a>
<FONT color="green">008</FONT>    package org.dellroad.stuff.main;<a name="line.8"></a>
<FONT color="green">009</FONT>    <a name="line.9"></a>
<FONT color="green">010</FONT>    import java.io.EOFException;<a name="line.10"></a>
<FONT color="green">011</FONT>    import java.io.File;<a name="line.11"></a>
<FONT color="green">012</FONT>    import java.util.ArrayList;<a name="line.12"></a>
<FONT color="green">013</FONT>    <a name="line.13"></a>
<FONT color="green">014</FONT>    import org.gnu.readline.Readline;<a name="line.14"></a>
<FONT color="green">015</FONT>    import org.gnu.readline.ReadlineLibrary;<a name="line.15"></a>
<FONT color="green">016</FONT>    import org.slf4j.Logger;<a name="line.16"></a>
<FONT color="green">017</FONT>    import org.slf4j.LoggerFactory;<a name="line.17"></a>
<FONT color="green">018</FONT>    <a name="line.18"></a>
<FONT color="green">019</FONT>    /**<a name="line.19"></a>
<FONT color="green">020</FONT>     * Support superclass for command line classes.<a name="line.20"></a>
<FONT color="green">021</FONT>     */<a name="line.21"></a>
<FONT color="green">022</FONT>    public abstract class MainClass {<a name="line.22"></a>
<FONT color="green">023</FONT>    <a name="line.23"></a>
<FONT color="green">024</FONT>        protected final Logger log = LoggerFactory.getLogger(getClass());<a name="line.24"></a>
<FONT color="green">025</FONT>    <a name="line.25"></a>
<FONT color="green">026</FONT>        protected MainClass() {<a name="line.26"></a>
<FONT color="green">027</FONT>        }<a name="line.27"></a>
<FONT color="green">028</FONT>    <a name="line.28"></a>
<FONT color="green">029</FONT>        /**<a name="line.29"></a>
<FONT color="green">030</FONT>         * Subclass main implementation. This method is free to throw exceptions; these will<a name="line.30"></a>
<FONT color="green">031</FONT>         * be displayed on standard error and converted into non-zero exit values.<a name="line.31"></a>
<FONT color="green">032</FONT>         *<a name="line.32"></a>
<FONT color="green">033</FONT>         * @return exit value<a name="line.33"></a>
<FONT color="green">034</FONT>         */<a name="line.34"></a>
<FONT color="green">035</FONT>        public abstract int run(String[] args) throws Exception;<a name="line.35"></a>
<FONT color="green">036</FONT>    <a name="line.36"></a>
<FONT color="green">037</FONT>        /**<a name="line.37"></a>
<FONT color="green">038</FONT>         * Enter command loop. Commands are read using GNU libreadline and handed off<a name="line.38"></a>
<FONT color="green">039</FONT>         * to {@link #handleCommand} for processing.<a name="line.39"></a>
<FONT color="green">040</FONT>         */<a name="line.40"></a>
<FONT color="green">041</FONT>        protected void commandLoop(String appName, String prompt) throws Exception {<a name="line.41"></a>
<FONT color="green">042</FONT>    <a name="line.42"></a>
<FONT color="green">043</FONT>            // Setup readline<a name="line.43"></a>
<FONT color="green">044</FONT>            try {<a name="line.44"></a>
<FONT color="green">045</FONT>                Readline.load(ReadlineLibrary.GnuReadline);<a name="line.45"></a>
<FONT color="green">046</FONT>            } catch (UnsatisfiedLinkError e) {<a name="line.46"></a>
<FONT color="green">047</FONT>                // ignore<a name="line.47"></a>
<FONT color="green">048</FONT>            }<a name="line.48"></a>
<FONT color="green">049</FONT>            Readline.initReadline(appName);<a name="line.49"></a>
<FONT color="green">050</FONT>            Readline.setThrowExceptionOnUnsupportedMethod(false);<a name="line.50"></a>
<FONT color="green">051</FONT>    <a name="line.51"></a>
<FONT color="green">052</FONT>            // Read init file(s)<a name="line.52"></a>
<FONT color="green">053</FONT>            ArrayList&lt;String&gt; files = new ArrayList&lt;String&gt;(3);<a name="line.53"></a>
<FONT color="green">054</FONT>            String var = System.getenv("INPUTRC");<a name="line.54"></a>
<FONT color="green">055</FONT>            if (var != null)<a name="line.55"></a>
<FONT color="green">056</FONT>                files.add(var);<a name="line.56"></a>
<FONT color="green">057</FONT>            String home = System.getProperty("user.home");<a name="line.57"></a>
<FONT color="green">058</FONT>            if (home != null)<a name="line.58"></a>
<FONT color="green">059</FONT>                files.add(new File(new File(home), ".inputrc").getAbsolutePath());<a name="line.59"></a>
<FONT color="green">060</FONT>            files.add("/etc/.inputrc");<a name="line.60"></a>
<FONT color="green">061</FONT>            for (String file : files) {<a name="line.61"></a>
<FONT color="green">062</FONT>                try {<a name="line.62"></a>
<FONT color="green">063</FONT>                    Readline.readInitFile(file);<a name="line.63"></a>
<FONT color="green">064</FONT>                } catch (Exception e) {<a name="line.64"></a>
<FONT color="green">065</FONT>                    // ignore<a name="line.65"></a>
<FONT color="green">066</FONT>                }<a name="line.66"></a>
<FONT color="green">067</FONT>            }<a name="line.67"></a>
<FONT color="green">068</FONT>    <a name="line.68"></a>
<FONT color="green">069</FONT>            // Read history file<a name="line.69"></a>
<FONT color="green">070</FONT>            String historyFile = new File(new File(System.getProperty("user.home")), "." + appName + "_history").getAbsolutePath();<a name="line.70"></a>
<FONT color="green">071</FONT>            try {<a name="line.71"></a>
<FONT color="green">072</FONT>                Readline.readHistoryFile(historyFile);<a name="line.72"></a>
<FONT color="green">073</FONT>            } catch (Exception e) {<a name="line.73"></a>
<FONT color="green">074</FONT>                // ignore<a name="line.74"></a>
<FONT color="green">075</FONT>            }<a name="line.75"></a>
<FONT color="green">076</FONT>    <a name="line.76"></a>
<FONT color="green">077</FONT>            // Main loop<a name="line.77"></a>
<FONT color="green">078</FONT>            try {<a name="line.78"></a>
<FONT color="green">079</FONT>                while (true) {<a name="line.79"></a>
<FONT color="green">080</FONT>    <a name="line.80"></a>
<FONT color="green">081</FONT>                    // Read next line<a name="line.81"></a>
<FONT color="green">082</FONT>                    String line;<a name="line.82"></a>
<FONT color="green">083</FONT>                    try {<a name="line.83"></a>
<FONT color="green">084</FONT>                        line = Readline.readline(prompt);<a name="line.84"></a>
<FONT color="green">085</FONT>                    } catch (EOFException e) {<a name="line.85"></a>
<FONT color="green">086</FONT>                        break;<a name="line.86"></a>
<FONT color="green">087</FONT>                    }<a name="line.87"></a>
<FONT color="green">088</FONT>    <a name="line.88"></a>
<FONT color="green">089</FONT>                    // No input?<a name="line.89"></a>
<FONT color="green">090</FONT>                    if (line == null)<a name="line.90"></a>
<FONT color="green">091</FONT>                        continue;<a name="line.91"></a>
<FONT color="green">092</FONT>    <a name="line.92"></a>
<FONT color="green">093</FONT>                    // Update history<a name="line.93"></a>
<FONT color="green">094</FONT>                    Readline.addToHistory(line);<a name="line.94"></a>
<FONT color="green">095</FONT>    <a name="line.95"></a>
<FONT color="green">096</FONT>                    // Execute line<a name="line.96"></a>
<FONT color="green">097</FONT>                    if (!this.handleCommand(line))<a name="line.97"></a>
<FONT color="green">098</FONT>                        break;<a name="line.98"></a>
<FONT color="green">099</FONT>                }<a name="line.99"></a>
<FONT color="green">100</FONT>            } finally {<a name="line.100"></a>
<FONT color="green">101</FONT>    <a name="line.101"></a>
<FONT color="green">102</FONT>                // Save history<a name="line.102"></a>
<FONT color="green">103</FONT>                try {<a name="line.103"></a>
<FONT color="green">104</FONT>                    Readline.writeHistoryFile(historyFile);<a name="line.104"></a>
<FONT color="green">105</FONT>                } catch (Exception e) {<a name="line.105"></a>
<FONT color="green">106</FONT>                    // ignore<a name="line.106"></a>
<FONT color="green">107</FONT>                }<a name="line.107"></a>
<FONT color="green">108</FONT>    <a name="line.108"></a>
<FONT color="green">109</FONT>                // Clean up<a name="line.109"></a>
<FONT color="green">110</FONT>                Readline.cleanup();<a name="line.110"></a>
<FONT color="green">111</FONT>            }<a name="line.111"></a>
<FONT color="green">112</FONT>        }<a name="line.112"></a>
<FONT color="green">113</FONT>    <a name="line.113"></a>
<FONT color="green">114</FONT>        /**<a name="line.114"></a>
<FONT color="green">115</FONT>         * Callback used by {@link #commandLoop}.<a name="line.115"></a>
<FONT color="green">116</FONT>         *<a name="line.116"></a>
<FONT color="green">117</FONT>         * &lt;p&gt;<a name="line.117"></a>
<FONT color="green">118</FONT>         * The implementation in {@link MainClass} just returns {@code false}.<a name="line.118"></a>
<FONT color="green">119</FONT>         *<a name="line.119"></a>
<FONT color="green">120</FONT>         * @return true to continue reading the next command, false to exit<a name="line.120"></a>
<FONT color="green">121</FONT>         */<a name="line.121"></a>
<FONT color="green">122</FONT>        protected boolean handleCommand(String line) throws Exception {<a name="line.122"></a>
<FONT color="green">123</FONT>            return false;<a name="line.123"></a>
<FONT color="green">124</FONT>        }<a name="line.124"></a>
<FONT color="green">125</FONT>    <a name="line.125"></a>
<FONT color="green">126</FONT>        /**<a name="line.126"></a>
<FONT color="green">127</FONT>         * Display the usage message to standard error.<a name="line.127"></a>
<FONT color="green">128</FONT>         */<a name="line.128"></a>
<FONT color="green">129</FONT>        protected abstract void usageMessage();<a name="line.129"></a>
<FONT color="green">130</FONT>    <a name="line.130"></a>
<FONT color="green">131</FONT>        /**<a name="line.131"></a>
<FONT color="green">132</FONT>         * Print the usage message and exit with exit value 1.<a name="line.132"></a>
<FONT color="green">133</FONT>         */<a name="line.133"></a>
<FONT color="green">134</FONT>        protected void usageError() {<a name="line.134"></a>
<FONT color="green">135</FONT>            usageMessage();<a name="line.135"></a>
<FONT color="green">136</FONT>            System.exit(1);<a name="line.136"></a>
<FONT color="green">137</FONT>        }<a name="line.137"></a>
<FONT color="green">138</FONT>    <a name="line.138"></a>
<FONT color="green">139</FONT>        /**<a name="line.139"></a>
<FONT color="green">140</FONT>         * Emit an error message an exit with exit value 1.<a name="line.140"></a>
<FONT color="green">141</FONT>         */<a name="line.141"></a>
<FONT color="green">142</FONT>        protected final void errout(String message) {<a name="line.142"></a>
<FONT color="green">143</FONT>            System.err.println(getClass().getSimpleName() + ": " + message);<a name="line.143"></a>
<FONT color="green">144</FONT>            System.exit(1);<a name="line.144"></a>
<FONT color="green">145</FONT>        }<a name="line.145"></a>
<FONT color="green">146</FONT>    <a name="line.146"></a>
<FONT color="green">147</FONT>        /**<a name="line.147"></a>
<FONT color="green">148</FONT>         * Parse command line flags of the form {@code -Dname=value} and set the corresponding system properties.<a name="line.148"></a>
<FONT color="green">149</FONT>         * Parsing stops at the first argument not starting with a dash (or {@code --}).<a name="line.149"></a>
<FONT color="green">150</FONT>         *<a name="line.150"></a>
<FONT color="green">151</FONT>         * @return command line with all the property-setting flags removed<a name="line.151"></a>
<FONT color="green">152</FONT>         */<a name="line.152"></a>
<FONT color="green">153</FONT>        protected String[] parsePropertyFlags(String[] args) {<a name="line.153"></a>
<FONT color="green">154</FONT>            ArrayList&lt;String&gt; list = new ArrayList&lt;String&gt;(args.length);<a name="line.154"></a>
<FONT color="green">155</FONT>            boolean done = false;<a name="line.155"></a>
<FONT color="green">156</FONT>            for (String arg : args) {<a name="line.156"></a>
<FONT color="green">157</FONT>                if (done) {<a name="line.157"></a>
<FONT color="green">158</FONT>                    list.add(arg);<a name="line.158"></a>
<FONT color="green">159</FONT>                    continue;<a name="line.159"></a>
<FONT color="green">160</FONT>                }<a name="line.160"></a>
<FONT color="green">161</FONT>                if (arg.equals("--") || arg.length() == 0 || arg.charAt(0) != '-') {<a name="line.161"></a>
<FONT color="green">162</FONT>                    list.add(arg);<a name="line.162"></a>
<FONT color="green">163</FONT>                    done = true;<a name="line.163"></a>
<FONT color="green">164</FONT>                    continue;<a name="line.164"></a>
<FONT color="green">165</FONT>                }<a name="line.165"></a>
<FONT color="green">166</FONT>                if (arg.startsWith("-D")) {<a name="line.166"></a>
<FONT color="green">167</FONT>                    int eq = arg.indexOf('=');<a name="line.167"></a>
<FONT color="green">168</FONT>                    if (eq &lt; 3)<a name="line.168"></a>
<FONT color="green">169</FONT>                        usageError();<a name="line.169"></a>
<FONT color="green">170</FONT>                    System.setProperty(arg.substring(2, eq), arg.substring(eq + 1));<a name="line.170"></a>
<FONT color="green">171</FONT>                    continue;<a name="line.171"></a>
<FONT color="green">172</FONT>                }<a name="line.172"></a>
<FONT color="green">173</FONT>                list.add(arg);<a name="line.173"></a>
<FONT color="green">174</FONT>            }<a name="line.174"></a>
<FONT color="green">175</FONT>            return list.toArray(new String[list.size()]);<a name="line.175"></a>
<FONT color="green">176</FONT>        }<a name="line.176"></a>
<FONT color="green">177</FONT>    <a name="line.177"></a>
<FONT color="green">178</FONT>        /**<a name="line.178"></a>
<FONT color="green">179</FONT>         * Invokes {@link #run}, catching any exceptions thrown and exiting with a non-zero<a name="line.179"></a>
<FONT color="green">180</FONT>         * value if and only if an exception was caught.<a name="line.180"></a>
<FONT color="green">181</FONT>         * &lt;p/&gt;<a name="line.181"></a>
<FONT color="green">182</FONT>         * &lt;p&gt;<a name="line.182"></a>
<FONT color="green">183</FONT>         * The concrete class' {@code main()} method should invoke this method.<a name="line.183"></a>
<FONT color="green">184</FONT>         * &lt;/p&gt;<a name="line.184"></a>
<FONT color="green">185</FONT>         */<a name="line.185"></a>
<FONT color="green">186</FONT>        protected void doMain(String[] args) {<a name="line.186"></a>
<FONT color="green">187</FONT>            int exitValue = 1;<a name="line.187"></a>
<FONT color="green">188</FONT>            try {<a name="line.188"></a>
<FONT color="green">189</FONT>                exitValue = run(args);<a name="line.189"></a>
<FONT color="green">190</FONT>            } catch (Throwable t) {<a name="line.190"></a>
<FONT color="green">191</FONT>                t.printStackTrace(System.err);<a name="line.191"></a>
<FONT color="green">192</FONT>            } finally {<a name="line.192"></a>
<FONT color="green">193</FONT>                System.exit(exitValue);<a name="line.193"></a>
<FONT color="green">194</FONT>            }<a name="line.194"></a>
<FONT color="green">195</FONT>        }<a name="line.195"></a>
<FONT color="green">196</FONT>    }<a name="line.196"></a>
<FONT color="green">197</FONT>    <a name="line.197"></a>




























































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